An improved compact model of the electrical behaviour of the 5-contact vertical Hall-effect device

作者:Madec Morgan*; Schell Jean Baptiste; Kammerer Jean Baptiste; Lallement Christophe; Hebrard Luc
来源:Analog Integrated Circuits and Signal Processing, 2014, 81(3): 677-691.
DOI:10.1007/s10470-014-0438-2

摘要

This paper presents the improvement of an existing design-oriented compact model of the 5-contact vertical Hall-effect sensor integrated in CMOS technology. Such a model should facilitate the work of designers, permitting them to simulate the sensor, the biasing and processing electronics together with the same electrical simulator. Focus is put on the main aspects that alter the electrical response of the sensor: modulation of the conduction channel due to the bias-dependent space charge region thickness, saturation of carrier velocity, asymmetries, and effective channel conduction thickness. The model has been achieved with a subtle mix of theoretical considerations, numerical simulations performed with COMSOL Multiphysics(A (R)) and experimental data. The parameters extraction procedure is also discussed. The model has been validated on experimental data gathered from two devices, one fabricated in a low-voltage CMOS technology and the other one in a high-voltage CMOS technology. Then, the model is used in order to study offset issues in VHD with external measurement contacts, i.e. VHD integrated in the shallow N-well of low-voltage technologies, and the way the spinning current technique can be used to suppress this offset. A new spinning-current technique is proposed for such a VHD. The simulation results are in perfect accordance with the analytical study. They pave the way for the design of an optimized readout circuitry that may improve the sensor sensitivity while maintaining a very low offset.

  • 出版日期2014-12