基于摄动法研究短沟道SOI MOSFET亚阈值特性

Regular Perturbation Method for Studying the Subthreshold Characteristics of Short Channel SOI MOSFETs

摘要: 提出了一种新的方法对短沟道SOI MOSFETs亚阈区的二维表面势的解析模型进行了改进, 即摄动法.由于在短沟道SOI MOSFETs中不仅需要计及不可动的电离杂质, 而且需要考虑自由载流子的数量和分布的影响.利用摄动法求解非线性泊松方程可以得到短沟道SOI MOSFETs二维的表面势解析模型.通过与二维数值模拟器MEDICI模拟结果比较, 证明了在亚阈区改进模型所得的结果比只计及不可动的电离杂质的SOI MOSFETs模型所得的结果吻合更好.

Abstract: A new method for studying the subthreshold characteristics of SOI MOSFETs is presented, which is called regular perturbation method.When the characeristics of SOI MOSFETs is being analyzed, we should consider not only the effect of the ionization impurity, but also the effect of the number and distributing of carriers. The analytical model of the SOI MOSFETs's surface voltage can be obtained by solving non-linear Possion equation with the “regular perturbation method”. The result of the model are verified with the numerical simulation.It can be concluded that the new model is better than the old model which only take account for the effect of the ionization impurity.