A New Design of a Single-Device 3D Hall Sensor: Cross-Shaped 3D Hall Sensor

• Published in: Sensors (Basel, Switzerland) Switzerland), 2018-04, Vol.18 (4), p.1065
• Main Authors: Tang, Wei, Lyu, Fei, Wang, Dunhui, Pan, Hongbing
• Format: Article
• Language: English
• Subjects: cross-shaped 3D Hall device; Hall effect; P-type layers; Sensitivity; Sensors; Thickness; three-contact Hall device; Two dimensional models
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s18041065

In this paper, a new single-device three-dimensional (3D) Hall sensor called a cross-shaped 3D Hall device is designed based on the five-contact vertical Hall device. Some of the device parameters are based on 0.18 μm BCDlite technology provided by GLOBALFOUNDRIES. Two-dimensional (2D) and 3D finite element models implemented in COMSOL are applied to understand the device behavior under a constant magnetic field. Besides this, the influence of the sensing contacts, active region's depth, and P-type layers are taken into account by analyzing the distribution of the voltage along the top edge and the current density inside the devices. Due to the short-circuiting effect, the sensing contacts lead to degradation in sensitivities. The P-type layers and a deeper active region in turn are responsible for the improvement of sensitivities. To distinguish the P-type layer from the active region which plays the dominant role in reducing the short-circuiting effect, the current-related sensitivity of the top edge ( ) is defined. It is found that the short-circuiting effect fades as the depth of the active region grows. Despite the P-type layers, the behavior changes a little. When the depth of the active region is 7 μm and the thickness of the P-type layers is 3 μm, the sensitivities in the , , and directions can reach 91.70 V/AT, 92.36 V/AT, and 87.10 V/AT, respectively.