3-Axis Hall Sensor Fabricated by Microassembly Technique

Abstract

We have developed a three-axis p-Si Hall sensor fabricated by microassembly technique of single crystalline silicon structure using a polyimide/metal bimorph cantilever. The 3-axis magnetic flux density can be detected with independent three devices which are X, Y and Z device. These three devices are designed to set into 800μm area and 300μm height cube after microassembly. The microassembly technique consists of the bending of polyimide/metal bimorph cantilever, the planarization of diced silicon sidewalls, and the bonding each axis device to the planarized silicon sidewalls with polyimide interlayer. The measured characteristics of the sensor were as follows, the magnetic sensitivities of each axis device were from 11.18 to 14.91mV/T, the product sensitivities were from 223.6 to 298.2V/AT. Though the cross axis sensitivity of X vs. Z, Y vs. Z and X vs. Y were 3.1%f.s., 3.8%f.s. and −1.1%f.s., respectively, it could be corrected to less than 0.5%f.s..