Physical model of floating body effects and its suppression study in fully depleted SOI MOSFETs

A new analytical model for SOI MOSFET with floating-body-effect(FBE) is developed to described the SOI MOSFET's strong inversion current characteristics. Considering all current components, the model can explain the physical mechanism of the current kink and breakdown phenomena as well as the dependence of I-V characteristics on various bias and channel length successfully. Based on this model, the dependence of FBE on several device parameters is studied. The results show that lowing source/drain doping decreasing minority-carrier life time optimizing the silicon film thickness and reducing channel doping will effectively suppress the FBE with much improved breakdown voltage characteristics. The experiments corresponding to the suppression of FBE with LDD&LDS structure and channel defect engineering, etc., demonstrate the calculated analysis, thereby enabling the theoretical result's realization in CMOS/SOI technology.EI02-3240-2473