The aim of this work was to optimize the shape of the cross-shaped Hall devices with regard to noise generated on sensing contacts. We have performed systematical experimental and numerical study of the influence of the geometry of the cross shaped Hall devices on the electrical low frequency noise measured on the sensing and driving current contacts. Based on our numerical calculations of the current density distribution (Finite Elements Method) we have designed several samples with various geometry/shape and dimensions in the 10 μm-200 μm range. Hall devices were fabricated on GaAs-based pseudomorphic heterostructures. Presented experimental results are in good agreement with our calculations of the noise power density based on electrical network theory and references therein. These results enable us to optimize the geometry of the devices giving us in the best case the reduction of the low frequency noise power density by ca -10 dB as compared to a standard Greek cross of identical size. This purely geometrical effect is independent of the sample physical structure and depends only on the sample shape. These results can be applied to any planar Si or III-V based semiconductor Hall device.
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