Nc-Si: Study On The Characteristics Of H/c-Si Heterojunction Silicon Magneto-sensitive Triode

In this paper, the silicon magnetic sensitivity transistor(SMST) with nc-Si:H/c-Si heterojunction is constructed based on the Micro-Electro-Mechanical Systems(MEMS)and Plasma Enhanced Chemical Vapor Deposition(PECVD), the structure owns a base(B), a collector(C) and a emitter(E), which the SMST emitter junction is nc-Si:H(n)/c-Si(p) heterojunction. Through the theoretical analysis of the heterojunction high injection ratio characteristics, the working principle of the SMST with nc-Si:H/c-Si heterojunction is given, this structure can improve the magnetic sensitive characteristic and temperature characteristic of the SMST by theoretical analysis. On this basis, the ATLAS software was used to establish the simulation structure model of the SMST with nc-Si:H/c-Si heterojunction, which compared with corresponding characteristic of the SMST with homojunction by analyzing IC-VCE property, magnetic property and temperature property, and study the influence of the base region length(L), the base region width(w) and the collector size(SC) on the property of the SMST with nc-Si:H/c-Si heterojunction, and the structure's geometric parameters are optimized.Based on the above, this paper achieved the design, fabrication and packaging of the SMST with nc-Si:H/c-Si heterojunction chip on the p-type <100> orientation monocrystalline silicon substrate with high resistivity(?>1000 ?·cm).At room temperature, studying the electrical characteristic, magnetic sensitive characteristic and temperature characteristic of the SMST with nc-Si:H/c-Si heterojunction by adopting semiconductor characteristic analysis system(KEITHLEY4200), magnetic field generator system(CH-100) and high/low temperature test chamber(OBIS GDJS100LG-G), and analysis the impact of the base region length(L)on the characteristic. The voltage magnetic sensitivities of the SMST with nc-Si:H/c-Si heterojunction with the base lengthes(L) of 140 ?m, 180 ?m and 200 ?m are 100.06 m V/T, 101.68 m V/T and 96.98 m V/T respectively, where VCE=5.0 V, Ib=6.0 m A, and the collector current temperature coefficients ?C are 341.7 ppm/?, 27.7 ppm/? and 355.7ppm/? respectively. The experimental results show that the SMST with nc-Si:H/c-Si heterojunction has high magnetic sensitivity and better temperature characteristic with the length of base(L) is 180 ?m.