The influence of strained SiGe thin layer and correlative structure parameters on sub-threshold characteristics of SiGe PMOSFETs

Sub-threshold characteristics of strained SiGe PMOSFETs and Si PMOSFETs are theoretically analyzed with simplified but effective models, then are simulated and compared by using a two-dimensional simulator. Sub-threshold current and sub-threshold slope varying with vertical structure parameters are also studied. Simulation results are well consistent with the theoretical analysis, and show that the sub-threshold characteristics of strained SiGe PMOSFETs, which are worse than those of Si PMOSFETs, are sensitive to vertical structure parameters and worth carefully paying attention to.