| This paper designs a monolithic integrated three dimensional?3D?magnetic field sensor based on micro-electromechanical systems?MEMS?technology and complementary metal-oxide-semiconductor?CMOS?process.This structure consists of two silicon magnetic sensitive transistor?SMST?differential structures,a Hall magnetic field sensor and a magnetism collected structure with high permeability.One of the differential structures which constructed by SMST-1 and SMST-3 is could realize the measurement of the applied magnetic field component Bx in x-direction,and another differential structure composed of the SMST-2 and SMST-4 also could accomplish the measurement of applied magnetic field component By in y-direction.Based on the Hall effect and the principle of the magnetism,the Hall magnetic field sensor and the magnetism collected structure are used to measure the z-direction component Bz of the applied magnetic field.The magnetic field is amplified by the magnetism collected structure,which can improve the magnetic sensitivity of the Hall magnetic field sensor in z-direction.On that basis,TCAD-Atlas and ANSYS were used to establish the simulation model of monolithic integrated 3D magnetic field sensor and high magnetic permeability magnetism collected structure,respectively,and simulation analysis were carried on.The monolithic integrated 3D magnetic field sensor chip layouts were designed by L-Edit integrated circuit layout design software.The monolithic integrated3D sensor chips were fabricated on p-type<100>crystal orientation high resistance silicon wafer based on MEMS technology and CMOS process.And the 3D sensor chips were packaged by inner wire bonding technology.At room temperature?300K?,the IC-VCE characteristic,magnetic characteristic and temperature characteristic of the sensor were studied by a semiconductor characterization system?KEITHLEY 4200?,a high precision magnetic field generator?CH-100?and a temperature test system,respectively.The experiment results indicate that when the power supply voltage VDD is 5.0 V and the base injection current IB is8.0mA,the magnetic sensitivities of the sensor in the x,y and z axes directions are107.7mV/T?103.7mV/T and 108.6mV/T,respectively.The experimental results show that the monolithic integrated 3D magnetic field sensor can be used to measure three components?Bx,By and Bz?of space magnetic field,and has a low cross-interference phenomenon and good consistency,which lays an significant foundation for further research on integrated sensor. |
PDF Full Text Request