Tang Wei, Lyu Fei, Wang Dunhui, Pan Hongbing
School of Physics, Nanjing University, Nanjing 210093, China.
School of Electric Science & Engineering, Nanjing University, Nanjing 210093, China.
Sensors (Basel). 2018 Apr 2;18(4):1065. 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.
本文基于五触点垂直霍尔器件设计了一种新型的单器件三维(3D)霍尔传感器,称为十字形3D霍尔器件。器件的一些参数基于格芯(GLOBALFOUNDRIES)提供的0.18μm BCDlite技术。利用COMSOL中实现的二维(2D)和三维有限元模型来了解器件在恒定磁场下的行为。除此之外,通过分析器件顶部边缘的电压分布和内部电流密度,考虑了传感触点、有源区深度和P型层的影响。由于短路效应,传感触点会导致灵敏度下降。P型层和更深的有源区反过来又有助于提高灵敏度。为了区分在降低短路效应中起主导作用的有源区和P型层,定义了顶部边缘的电流相关灵敏度()。发现随着有源区深度的增加,短路效应逐渐减弱。尽管有P型层,行为变化不大。当有源区深度为7μm且P型层厚度为3μm时,在x、y和z方向上的灵敏度分别可达91.70V/AT、92.36V/AT和87.10V/AT。