Magnetic Micro Sensors with Two Magnetic Field Effect Transistors Fabricated Using the Commercial Complementary Metal Oxide Semiconductor Process

• Published in: Sensors (Basel, Switzerland) Switzerland), 2020-08, Vol.20 (17), p.4731
• Main Authors: Chen, Wei-Ren, Tsai, Yao-Chuan, Shih, Po-Jen, Hsu, Cheng-Chih, Dai, Ching-Liang
• Format: Article
• Language: English
• Subjects: CMOS; Collectors; Field effect transistors; magnetic field effect transistor; Magnetic fields; magnetic microsensor; MEMS; Metal oxide semiconductors; Metal oxides; Microelectromechanical systems; Noise; Printed circuit boards; Semiconductor devices; Semiconductors; Sensitivity; Sensors; Three axis; Transistors; Unmanned aerial vehicles
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s20174731

The fabrication and characterization of a magnetic micro sensor (MMS) with two magnetic field effect transistors (MAGFETs) based on the commercial complementary metal oxide semiconductor (CMOS) process are investigated. The magnetic micro sensor is a three-axis sensing type. The structure of the magnetic microsensor is composed of an x/y-MAGFET and a z-MAGFET. The x/y-MAGFET is employed to sense the magnetic field (MF) in the x- and y-axis, and the z-MAGFET is used to detect the MF in the z-axis. To increase the sensitivity of the magnetic microsensor, gates are introduced into the two MAGFETs. The sensing current of the MAGFET enhances when a bias voltage is applied to the gates. The finite element method software Sentaurus TCAD was used to analyze the MMS’s performance. Experiments show that the MMS has a sensitivity of 182 mV/T in the x-axis MF and a sensitivity of 180 mV/T in the y-axis MF. The sensitivity of the MMS is 27.8 mV/T in the z-axis MF.