Investigation of the Sensitivity of a Novel Vertical Hall Device Based on the Buried Layer

Abstract

This article proposes a novel five-contact vertical Hall device (VHD) with a buried layer (BL-5CVHD) compatible with a standard bipolar-CMOS-DMOS (BCD) process. VHDs sense a parallel magnetic field. Therefore, the transverse currents in the active region of VHDs determine the magnetic sensitivity. The BL provides a longitudinal electric field for majority carriers to form a transverse current, improving sensitivity. Through dedicated numerical simulations, we observe that the BL leads to a symmetrical distribution of the Hall potential, presenting better transverse currents. The geometric parameters of the BL-5CVHD are then further analyzed and optimized. Ultimately, the optimized BL-5CVHD voltage-related sensitivity reaches 10.53% <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{T}^{-{1}}$ </tex-math></inline-formula> . Meanwhile, the offset voltage decreases to 0.55 mV.