Preparation Of FeGa Films By Ion Beam Sputtering And Their Magnetic Sensing Properties

Magnetic sensor is an important part in the development of the thing of Internet.The most obvious characteristics of modern magnetic sensors are high sensitivity,miniaturization, integration, low-cost and so on. The most commonly used sensors(Hall sensor, giant magnetoresisitive sensor, flux gate and optical pumping magnetometer) in magnetic field detection have some limitations in function and size.So it is meaning to investigate integral and sensitive magnetic sensors.Recent years, some magnetic sensors based on magnetoelectric coupling effect composed by piezoelectricity and magnetostrictive arise people attention. According to some references, the magnetic resolution of Co Fe Si B/Al N magnetoelectric coupling senor made by MEMS technology can reach p T, which can be used in magnetoencephalogram and magnetocardiogram. However, selecting proper magnetostrictive materials can also increase the magnetoelectric effect, and it should be followed two principles. Firstly, the magnetostrictive effect should be enlarged which can regulate the coupling of the interface; secondly, the soft-magnetic properties should be optimized, which could enlarge the sensitivity of magnetic field detection. Normally, soft-magnetic ferrite is low-cost and widely used, but the coercivity and saturation magnetization is lower than metal materials. Terfenol-D has huge magnetostrictive effect, but it is so expensive and brittle, moreover, it is not suitable for tiny magnetic field detection. Some alloys like Permalloy and Co Fe Si B have good soft magnetic properties, but have small magnetostrictive coefficient. Fe Ga alloy is a kind of materials witch has both big magnetostrictive coefficient and good soft-magnetic properties. When the atom ratio is Fe80Ga20, the magnetostrictive can reach up to 400 ppm, the saturation magnetization can reach up to 1.7 T and the coercivity is lower than 100 Oe. It is an ideal material for making high-resolution magnetic sensor. For another hand, we used environmental friendly BNTO-BTO ceramics, and deposited Fe Ga on the surface. It is hopeful to obtain better magnetoelectric property and make a foundation for future sensors.In this work, we investigated the Fe Ga film by ion-sputtering deposition and developed the sensor applications. Firstly, we changed the thickness, sputtering space and the sputtering pressure, and obtain the technological parameter. Secondly, we successfully decreases the coercivity and got the anisotropy by adulteration and oblique sputtering, respectively. Finally, we researched the giant magnetoimpedance effect and magnetoelectric coupling effect by deposited the Fe Ga film on amorphous Fe Cu Nb Si B ribbon and 0.89(Bi0.5Na0.5)Ti O3-0.11 Ba Ti O3 piezoelectric ceramics. We find that the GMI effect can be the increased and the magnetoelectric effect can also be observed.