A Physically Based Analytical Modeling of Threshold Voltage Control for   Fully-Depleted SOI Double Gate NMOS-PMOS Flexible-FET
  In this work, we propose an explicit analytical equation to show the variation of top gate threshold voltage with respect to the JFET bottom gate voltage for a Flexible Threshold Voltage Field Effect Transistor (Flexible-FET) by solving 2-D Poisson's equation with appropriate boundary conditions, incorporating Young's parabolic approximation. The proposed model illustrates excellent match with the experimental results for both n-channel and p-channel 180nm Flexible-FETs. Threshold voltage variation with several important device parameters (oxide and silicon channel thickness, doping concentration) is observed which yields qualitative matching with results obtained from SILVACO simulations. 
Nadim Chowdhury, Zubair Al Azim, Imtiaz Ahmed, Iftikhar Ahmad Niaz,   Md. Hasibul Alam, Quazi D.M. Khosru
cond-mat.mtrl-sci