We analyzed the performance of Hall sensors with different Co-C ratios, deposited directly in nano-structured form, using Co2(CO)8 gas molecules, by focused electron or ion beam induced deposition. Due to the enhanced inter-grain scattering in these granular wires, the Extraordinary Hall Effect can be increased by two orders of magnitude with respect to pure Co, up to a current sensitivity of 1Ω/T. We show that the best magnetic field resolution at room temperature is obtained for Co ratios between 60% and 70% and is better than 1μT/Hz1/2. For an active area of the sensor of 200×200nm2, the room temperature magnetic flux resolution is ϕmin=2×10−5ϕ0, in the thermal noise frequency range, i.e. above 100 kHz.
@article{arxiv.0908.3028,
title = {Nano-Hall sensors with granular Co-C},
author = {Mihai Gabureac and Laurent Bernau and Ivo Utke and Giovanni Boero},
journal= {arXiv preprint arXiv:0908.3028},
year = {2016}
}