通过对全耗尽 SOI器件硅膜中的纵向电位分布采用准三阶近似 ,求解亚阈区的二维泊松方程 ,得到全耗尽器件的表面势公式 ;通过引入新的参数 ,对公式进行修正 ,建立深亚微米全耗尽器件的表面势模型 ,能够很好地描述漏感应势垒降低效应 .在此基础上 ,建立了亚阈漏电流模型 ,它能够很好的描述亚阈区的完整漏电流特性 ,模型计算结果与二维器件模拟软件 MEDICI的模拟结果相符 The quasi-third-order approximation of the longitudinal potential distribution in the silicon film of a fully depleted SOI device is used to solve the two-dimensional Poisson equation in the subthreshold region to obtain the surface potential equation of a fully depleted device. By introducing new parameters, After the correction and establishment of the surface potential model of fully depleted devices in deep submicron, it can well describe the effect of the reduction of leakage induced barrier. On this basis, a subthreshold leakage current model is established, which can well describe the Complete leakage current characteristics, model calculation results and simulations of two-dimensional device simulation software MEDICI simulation results