Magnetic and Magnetotransport Properties of Memory Sensors Based on Anisotropic Magnetoresistance

The magnetic and magnetoresistance properties of anisotropic magnetoresistance (AMR) sensors based on Wheatstone bridge (WB) with barber pole and conventional Hall bar structures were studied. The samples were prepared by using standard microlithography and sputter deposition techniques and then measured by magneto-optic Kerr effect and magneto transport methods. The advantages of the AMR sensor based on WB compared with Hall bar structure were discussed. It was observed that sensitivity was increased almost 15 times when sensors with the WB structures were used instead of Hall bar structures. Moreover, sensor stability was tested in various external magnetic fields with positive and negative polarities. The test results show that sensor response is stable even in various external magnetic fields up to 5000 Oe. The changes in sensitivity and output voltage were attributed to WB structure.